CO2-Promoted Catalytic Process Forming Higher Alcohols with Tunable Nature at Record Productivity

Converting syngas obtained from renewable or abundant feedstocks into higher alcohols (HA) is a potentially more sustainable route to these important chemicals and fuels than industrial technologies, but lacks a performing catalytic process to reach commercialization. Here, we show that moderate CO2 amounts (R=CO2/(CO+CO2)=0.12) in the feed raise the HA productivity over copper-iron catalysts carried on carbon nanofibers and promoted by potassium to a 3-fold higher level than the state of the art. CO2 promotes copper dispersion and thus the formation of activated CO species, as in traditional methanol synthesis. Still, since its vicinity to iron is boosted, CO insertion into growing hydrocarbon chains prevails on hydrogenation, translating positive effects to HA production. Cascade zeolite-catalyzed upgrading of methanol and olefins byproducts generates a breakthrough process forming 2.42 g(HA) h(-1) g(cat)(-1), which is 4-times superior to the best systems, and tuning the HA nature based on the aluminosilicate topology.